高能电子束辐照处理对几种进口水果表皮色泽的影响

以泰国青芒果(honeys)、澳大利亚红芒果(R2E2)和台湾二林种杨桃为试材,研究电子束辐照处理对果实表皮色泽的影响,为电子束辐照检疫进口水果提供参考依据。结果表明,三种水果经0.43、0.85、1.26、1.68 kGy剂量的电子束辐照后立即观测,未发现肉眼可见的色泽变化,但总色差计算分析表明,辐照处理可导致果实产生色差,其中以0.43 kGy处理的色差最小,1.68 kGy处理的最大。货架条件(15~25℃)存放7 d后,不同辐照剂量处理的果皮色泽表现出明显的差异,果皮出现褐变,且剂量越大,褐变指数越高,其中泰国青芒果的后熟黄化受到抑制。因此,建议台湾二林种杨桃的适宜辐照剂量应在0.43 kGy以下,泰国青芒果和澳大利亚红芒果的适宜辐照剂量应在0.85 kGy以下。统计分析色泽参数(L*、a*、b*)与辐照剂量的相关性发现,三种水果果皮的红/绿轴参数a*与辐照剂量存在显著相关,在评价辐照果实色泽中具有重要意义。

Effect of High Energy Electron Beam Irradiation on Epidermis Color of Certain Imported Fruits

In order to provide basis for irradiation use on quarantine of fresh fruits, effects of E-beam irradiation on skin color of mango （honeys, R2E2） and carambola were studied. Results showed that, macroscopical changes of fruits skin color were not occurred for those fruits which were just irradiated with doses of 0.43, 0.85, 1.26, 1.68 kGy. But the total color difference （△E） of fruits were detected, and 1.68 kGy treated fruits was higher than that of lower dose treated ones. After storage at shelf situation （15 -25 ℃ ） for 7 days, the differences of skin color of which were treated at different dosage were macroscopical. Skins browning were observed which increased with the higher doses, and the ripening of honeys was inhibited. These results indicated that, the appropriate irradiation dose for earambola would be under 0.43 kGy while those for mango （honeys, R2E2） would be under 0.85 kGy. In addition, the correlation analysis between values of L＊, a＊, b＊ and irradiation dose showed that a＊ plays an important role in evaluation of irradiated fruits color because it was significantly correlated with irradiation dose.